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You may be surprised to learn that dust storms that bring particles from the Sahara to European cities occur more often than you would assume. What you need to know about them, as well as how to protect yourself, is going to be presented here.
This week, dust from the Sahara was blown hundreds of kilometers to Athens, Greece, culminating in a remarkable natural phenomenon that gave the appearance of the Acropolis being located on Mars, at least for a brief while. This caused everything to have a reddish-orange hue.
Storms that bring dust from the Sahara into European cities are not uncommon and have been occurring for a number of years. The following is information that you should be aware of on how they develop, how they travel, and whether or not they pose a danger.
Describe the process by which a dust storm forms in the Sahara
Dust storms are caused by the passage of strong winds across the Sahara Desert, which is located in northern Africa, when the conditions are dry. DW was informed by Carlos Perez Garcia Pando, an expert on sand and dust at the Barcelona Supercomputing Center, that the sands of the desert are composed of a wide variety of particles.
Certain particles are hefty and of a big size. These are the initial particles that are taken up by strong winds, but they are not the particles that will eventually make their way to Europe by means of the Mediterranean Sea.
Instead, Garcia Pando said that as these bigger particles fall to the ground, their contact causes additional clumps of sand to break away, resulting in the dispersion of very microscopic dust particles. Due to the fact that they are so minute and light, these smaller particles are the ones that eventually drift across large distances into the atmosphere.
In order for these storms to take place, the circumstances must be dry. If they are not, the particles will cluster together and become too heavy to travel over long distances. The locations with the least amount of vegetation are the ones that are more likely to have sandstorms. This is because vegetation has the potential to interact with the wind and slow down a storm.
If these storms are carrying dust to Europe, what is the cause?
In the Sahara Desert, dust storms are occurring on a regular basis. However, in order for these storms to be able to blow thousands of miles north, they need to engage with a weather system that is capable of providing the powerful winds that are required to propel them across such substantial distances.
The majority of the time, a meteorological system with low pressure is responsible for transporting dust from the Sahara to Europe via the Mediterranean. According to Garcia Pando, these systems are energetic and result in powerful winds that blow in a counterclockwise direction. Usually, they take place in the springtime. These occurrences may also be caused by high-pressure weather systems, but the likelihood of this happening is lower.
In an email to DW, Stuart Evans, a dust specialist at the University of Buffalo in New York, said that the dust particles that eventually make their way to Europe are able to remain in the air for such a long period of time because they are much smaller than sand, which falls out of the air much more quickly.
“What arrives in Europe is a dust storm but not a sand storm,” he said to reporters.
What kind of a problem are these dust storms?
“This has happened repeatedly throughout history, dust is almost as old as the Earth,” stated Garcia Pando in his presentation. “It’s nothing new.”
In his explanation, he said that the purpose of investigating these dust storm incidents is not to scare people. On the contrary, he said that it is more important to comprehend the phenomena and to comprehend what it means for both civilization and the environment. According to his explanation, dust is not necessarily a negative thing. For instance, it acts as a kind of fertilizer to forests and seas, providing them with iron and phosphorus.
Since pre-industrial times, Garcia Pando said that there has been an increase in the quantity of dust that is present on Earth. This may be attributed, in large part, to the cultivation of land by humans, but also to the changing climate.
To illustrate how this works, he suggested that you picture a bit of dirt that has been crusted over. When you walk on dirt or when a vehicle drives over it, a large number of particles of dirt are released into the air, and “all of those particles are more easily affected by wind.”
In reference to climate change, he used the illustration of water sources that get dry as a result of a drought phenomenon. In his words, “the sediments that remain in the lake are very, very erosive and can be emitted very easily to the atmosphere.” This is something that happens after a lake has dried up.
However, at this point in time, experts are still uncertain as to whether or not climate change will result in an increase or decrease in the amount of wind that occurs on Earth. As a result, it is difficult to speculate on what the future may hold for dust storms.
“This is one of the key uncertainties that we have in projecting the future of the dust,” Garcia Pando said in his presentation. “Understanding how winds in different situations will evolve — not only the average wind, but also the extremes.”
Maintain your safety in the midst of a dust storm
Garcia Pando advised in the event that you find yourself trapped in a dust storm in Europe that you should adhere to the same recommendations that are made by specialists on days when the air quality is extremely poor. Dust is a respiratory threat; thus, put on a mask and refrain from participating in any outside sporting activity. People who suffer from respiratory problems are going to find this to be especially true.
